1. Field of the Invention
The present invention relates to a gimbal mechanism provided, for example, at a nose of a guided flying object to aim an image pick-up device at a target direction.
2. Description of the Related Art
In a gimbal mechanism used in a guided flying object, a drive motor and angle detector are arranged on each of Y and Z axes to drive an image pickup device about two axes (Y and X axes). In this structure, the drive motor and angle detector provide an obstacle to the movement of the image pickup device and the aperture of the image pickup device is restricted by that extent. In the present situation, more amount of light cannot be incident on the image pickup device and it is difficult to improve the performance of the image pickup device. In particular in the case where the gimbal mechanism of the above-mentioned structure is mounted at the nose of the flying object and used as a guided device, more restrictions are added due to its body size and mounting space. As a result, it is not possible to increase the aperture of the image pickup device and, any longer, to expect an improvement of a target acquisition capability.
The present invention provides a gimbal mechanism adapted to rotate a to-be-supported body (for example, an image pickup section) about mutually orthogonal first and second axes (for example, Y and Z axes), the gimbal mechanism comprising a support frame (for example, a gimbal) rotatably supporting the to-be-supported body about the first axis and having an extension place opposite to a mounting surface at least in a fixed position, one pair of support pieces (for example, support columns) fixed to a mounting surface to rotatably support the support frame about the second axis, a first motor (for example, a motor) mounted on the support frame to rotate the to-be-supported body about the first axis, a first angle sensor (for example, an angle detector) mounted on the support frame to detect a rotation angle of the to-be-supported body about the first axis, a second motor (for example, a magnet and coil unit) for imparting a drive force to a place of the support frame on a side of, and opposite to, the mounting surface to rotate the support frame, as a whole, about the second axis, and a second angle sensor (for example, a sensor head and rod) for detecting a rotation angle of the support frame about the second axis from a movement locus of a specific position defined by the rotation of the support frame about the second axis.
Additional objects and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The objects and advantages of the invention may be realized and obtained by means of the instrumentalities and combinations particularly pointed out hereinafter.